/*
- * Copyright (c) 2012 ARM Limited
+ * Copyright (c) 2012, 2015, 2017 ARM Limited
* All rights reserved.
*
* The license below extends only to copyright in the software and shall
* Authors: Ali Saidi
* Nathan Binkert
* Andreas Hansson
+ * Andreas Sandberg
*/
+#include "dev/dma_device.hh"
+
+#include <utility>
+
#include "base/chunk_generator.hh"
#include "debug/DMA.hh"
#include "debug/Drain.hh"
-#include "dev/dma_device.hh"
+#include "mem/port_proxy.hh"
#include "sim/system.hh"
DmaPort::DmaPort(MemObject *dev, System *s)
- : MasterPort(dev->name() + ".dma", dev), device(dev), sendEvent(this),
- sys(s), masterId(s->getMasterId(dev->name())),
- pendingCount(0), drainManager(NULL),
- inRetry(false)
+ : MasterPort(dev->name() + ".dma", dev),
+ device(dev), sys(s), masterId(s->getMasterId(dev)),
+ sendEvent([this]{ sendDma(); }, dev->name()),
+ pendingCount(0), inRetry(false)
{ }
void
delete state;
}
- // delete the request that we created and also the packet
- delete pkt->req;
+ // delete the packet
delete pkt;
// we might be drained at this point, if so signal the drain event
- if (pendingCount == 0 && drainManager) {
- drainManager->signalDrainDone();
- drainManager = NULL;
- }
+ if (pendingCount == 0)
+ signalDrainDone();
}
bool
DmaPort::recvTimingResp(PacketPtr pkt)
{
- // We shouldn't ever get a block in ownership state
- assert(!(pkt->memInhibitAsserted() && !pkt->sharedAsserted()));
+ // We shouldn't ever get a cacheable block in Modified state
+ assert(pkt->req->isUncacheable() ||
+ !(pkt->cacheResponding() && !pkt->hasSharers()));
handleResp(pkt);
PioDevice::init();
}
-unsigned int
-DmaDevice::drain(DrainManager *dm)
+DrainState
+DmaPort::drain()
{
- unsigned int count = pioPort.drain(dm) + dmaPort.drain(dm);
- if (count)
- setDrainState(Drainable::Draining);
- else
- setDrainState(Drainable::Drained);
- return count;
-}
-
-unsigned int
-DmaPort::drain(DrainManager *dm)
-{
- if (pendingCount == 0)
- return 0;
- drainManager = dm;
- DPRINTF(Drain, "DmaPort not drained\n");
- return 1;
+ if (pendingCount == 0) {
+ return DrainState::Drained;
+ } else {
+ DPRINTF(Drain, "DmaPort not drained\n");
+ return DrainState::Draining;
+ }
}
void
-DmaPort::recvRetry()
+DmaPort::recvReqRetry()
{
assert(transmitList.size());
trySendTimingReq();
}
-void
+RequestPtr
DmaPort::dmaAction(Packet::Command cmd, Addr addr, int size, Event *event,
uint8_t *data, Tick delay, Request::Flags flag)
{
// i.e. cache line size
DmaReqState *reqState = new DmaReqState(event, size, delay);
+ // (functionality added for Table Walker statistics)
+ // We're only interested in this when there will only be one request.
+ // For simplicity, we return the last request, which would also be
+ // the only request in that case.
+ RequestPtr req = NULL;
+
DPRINTF(DMA, "Starting DMA for addr: %#x size: %d sched: %d\n", addr, size,
event ? event->scheduled() : -1);
- for (ChunkGenerator gen(addr, size, peerBlockSize());
+ for (ChunkGenerator gen(addr, size, sys->cacheLineSize());
!gen.done(); gen.next()) {
- Request *req = new Request(gen.addr(), gen.size(), flag, masterId);
+
+ req = std::make_shared<Request>(
+ gen.addr(), gen.size(), flag, masterId);
+
+ req->taskId(ContextSwitchTaskId::DMA);
PacketPtr pkt = new Packet(req, cmd);
// Increment the data pointer on a write
// just created, for atomic this involves actually completing all
// the requests
sendDma();
+
+ return req;
}
void
}
return PioDevice::getMasterPort(if_name, idx);
}
+
+
+
+
+
+DmaReadFifo::DmaReadFifo(DmaPort &_port, size_t size,
+ unsigned max_req_size,
+ unsigned max_pending,
+ Request::Flags flags)
+ : maxReqSize(max_req_size), fifoSize(size),
+ reqFlags(flags), port(_port),
+ buffer(size),
+ nextAddr(0), endAddr(0)
+{
+ freeRequests.resize(max_pending);
+ for (auto &e : freeRequests)
+ e.reset(new DmaDoneEvent(this, max_req_size));
+
+}
+
+DmaReadFifo::~DmaReadFifo()
+{
+ for (auto &p : pendingRequests) {
+ DmaDoneEvent *e(p.release());
+
+ if (e->done()) {
+ delete e;
+ } else {
+ // We can't kill in-flight DMAs, so we'll just transfer
+ // ownership to the event queue so that they get freed
+ // when they are done.
+ e->kill();
+ }
+ }
+}
+
+void
+DmaReadFifo::serialize(CheckpointOut &cp) const
+{
+ assert(pendingRequests.empty());
+
+ SERIALIZE_CONTAINER(buffer);
+ SERIALIZE_SCALAR(endAddr);
+ SERIALIZE_SCALAR(nextAddr);
+}
+
+void
+DmaReadFifo::unserialize(CheckpointIn &cp)
+{
+ UNSERIALIZE_CONTAINER(buffer);
+ UNSERIALIZE_SCALAR(endAddr);
+ UNSERIALIZE_SCALAR(nextAddr);
+}
+
+bool
+DmaReadFifo::tryGet(uint8_t *dst, size_t len)
+{
+ if (buffer.size() >= len) {
+ buffer.read(dst, len);
+ resumeFill();
+ return true;
+ } else {
+ return false;
+ }
+}
+
+void
+DmaReadFifo::get(uint8_t *dst, size_t len)
+{
+ const bool success(tryGet(dst, len));
+ panic_if(!success, "Buffer underrun in DmaReadFifo::get()\n");
+}
+
+void
+DmaReadFifo::startFill(Addr start, size_t size)
+{
+ assert(atEndOfBlock());
+
+ nextAddr = start;
+ endAddr = start + size;
+ resumeFill();
+}
+
+void
+DmaReadFifo::stopFill()
+{
+ // Prevent new DMA requests by setting the next address to the end
+ // address. Pending requests will still complete.
+ nextAddr = endAddr;
+
+ // Flag in-flight accesses as canceled. This prevents their data
+ // from being written to the FIFO.
+ for (auto &p : pendingRequests)
+ p->cancel();
+}
+
+void
+DmaReadFifo::resumeFill()
+{
+ // Don't try to fetch more data if we are draining. This ensures
+ // that the DMA engine settles down before we checkpoint it.
+ if (drainState() == DrainState::Draining)
+ return;
+
+ const bool old_eob(atEndOfBlock());
+
+ if (port.sys->bypassCaches())
+ resumeFillFunctional();
+ else
+ resumeFillTiming();
+
+ if (!old_eob && atEndOfBlock())
+ onEndOfBlock();
+}
+
+void
+DmaReadFifo::resumeFillFunctional()
+{
+ const size_t fifo_space = buffer.capacity() - buffer.size();
+ const size_t kvm_watermark = port.sys->cacheLineSize();
+ if (fifo_space >= kvm_watermark || buffer.capacity() < kvm_watermark) {
+ const size_t block_remaining = endAddr - nextAddr;
+ const size_t xfer_size = std::min(fifo_space, block_remaining);
+ std::vector<uint8_t> tmp_buffer(xfer_size);
+
+ assert(pendingRequests.empty());
+ DPRINTF(DMA, "KVM Bypassing startAddr=%#x xfer_size=%#x " \
+ "fifo_space=%#x block_remaining=%#x\n",
+ nextAddr, xfer_size, fifo_space, block_remaining);
+
+ port.sys->physProxy.readBlob(nextAddr, tmp_buffer.data(), xfer_size);
+ buffer.write(tmp_buffer.begin(), xfer_size);
+ nextAddr += xfer_size;
+ }
+}
+
+void
+DmaReadFifo::resumeFillTiming()
+{
+ size_t size_pending(0);
+ for (auto &e : pendingRequests)
+ size_pending += e->requestSize();
+
+ while (!freeRequests.empty() && !atEndOfBlock()) {
+ const size_t req_size(std::min(maxReqSize, endAddr - nextAddr));
+ if (buffer.size() + size_pending + req_size > fifoSize)
+ break;
+
+ DmaDoneEventUPtr event(std::move(freeRequests.front()));
+ freeRequests.pop_front();
+ assert(event);
+
+ event->reset(req_size);
+ port.dmaAction(MemCmd::ReadReq, nextAddr, req_size, event.get(),
+ event->data(), 0, reqFlags);
+ nextAddr += req_size;
+ size_pending += req_size;
+
+ pendingRequests.emplace_back(std::move(event));
+ }
+}
+
+void
+DmaReadFifo::dmaDone()
+{
+ const bool old_active(isActive());
+
+ handlePending();
+ resumeFill();
+
+ if (old_active && !isActive())
+ onIdle();
+}
+
+void
+DmaReadFifo::handlePending()
+{
+ while (!pendingRequests.empty() && pendingRequests.front()->done()) {
+ // Get the first finished pending request
+ DmaDoneEventUPtr event(std::move(pendingRequests.front()));
+ pendingRequests.pop_front();
+
+ if (!event->canceled())
+ buffer.write(event->data(), event->requestSize());
+
+ // Move the event to the list of free requests
+ freeRequests.emplace_back(std::move(event));
+ }
+
+ if (pendingRequests.empty())
+ signalDrainDone();
+}
+
+DrainState
+DmaReadFifo::drain()
+{
+ return pendingRequests.empty() ? DrainState::Drained : DrainState::Draining;
+}
+
+
+DmaReadFifo::DmaDoneEvent::DmaDoneEvent(DmaReadFifo *_parent,
+ size_t max_size)
+ : parent(_parent), _done(false), _canceled(false), _data(max_size, 0)
+{
+}
+
+void
+DmaReadFifo::DmaDoneEvent::kill()
+{
+ parent = nullptr;
+ setFlags(AutoDelete);
+}
+
+void
+DmaReadFifo::DmaDoneEvent::cancel()
+{
+ _canceled = true;
+}
+
+void
+DmaReadFifo::DmaDoneEvent::reset(size_t size)
+{
+ assert(size <= _data.size());
+ _done = false;
+ _canceled = false;
+ _requestSize = size;
+}
+
+void
+DmaReadFifo::DmaDoneEvent::process()
+{
+ if (!parent)
+ return;
+
+ assert(!_done);
+ _done = true;
+ parent->dmaDone();
+}
projects / gem5.git / blobdiff